burke



(No Model.) 3V Sheets-Sheet 2.

o. G. BURKE. PRINTING TELBGRAPH.

No. 306,056. Patented 00L-'7, 1884.4

WITNESSES INVENTOR By his attorneys N Farms, PnmwLnlmmplmr. wamingxm. n.C.

(No Model.) 3 Sheets-Sheet 3.

G. G. BURKE. 1 PRINTING TBLBGRAPH.

No'. 306,056. [Patented 001;.7, 1884.

wlTNEssEs l' V lNvENToR y By LLS .Attorneys "Unirse Srarns Partnr triceCHARLES G. BURKE, OF RICHMOND HILL, NEV YORK.

PRINTING-'TELEGRAPi-i.

`.3PECIFICATION forming part of Letters Patent No. 306,056, datedOctober 7, 1884. 1

(No model.)

To all whom t may concern,.-

Be it known that I, CHARLES G. BURKE, a citizen of the United States,residing at Richmond Hill, in the county of Queens and State of NewYork, have invented certain new and useful Improvements inPrinting-Telegraphs, of which the following is a specification.

The invention relates to the class of electrical apparatus which isemployed 'for telegraphieally transmitting messages or dispatches over asingle main-line conductor, and obtaining a record of the same in theform of impressions of the characters constituting or embodying themessages or dispatches imprinted from one or more type-wheels; and italso relates to the method of transmitting and receiving the electricalimpulses whereby the communications are conveyed.

The object ofthe invention is to provide means for transmitting upon asingle mainline conductor electric impulses adapted to actuate thetype-wheels of a printing-telegraph instrument located at a distantstation, and to so organize the apparatus that impressions may be takenfrom either of the type-wheels at will, and in such a manner as toconstitute two distinct records, the operation of transmitting andreceiving two messages being carried on at the same time.

In carrying out the invention, it is preferred to construct theapparatus in substantially the following manner, and to operate the samein a manner which will be described in connection with the apparatus.

For the purpose of obtaining alternate electric currents adapted toactuate the escapement device of the receiving-instrument, apole-changing device is employed at thctransmitter, which is adapted toalternately connect the poles of two opposing batteries with themainline. The impulses thus transmitted are preferably caused totraverse an artificial resistance, which in effect, to a certain extent,diminishes their strength.

Two transmitting key-boards are employed in connection with thepole-changing device, which are adapted at the proper times to completethe connections of a shunt-circuit around the artificial resistance,provided a key of one of the key-boards be depressed. An increase in thestrength of the current occasioned in this manner is employed foreffecting an impression from one or the other of the receivingtype-wheels, accordingly as the key employed for effecting the increaseis located upon one or the other of the transmitting keyboards. It isobvious, however, that some means must be provided for causing the im-Vpulses of increased strength to be distributed between the press-magnetsof the two receiving type-wheels in their proper order, so that theimpulses of increased strength occasioned by depressing the keys of therespective keyboards shall be caused to traverse only the electro-magnetdesigned to effect an impression from the type-wheel corresponding tothat key-board. To accomplish this result, means are provided forcausing the circuit at the receiving-station to be completed from themain line first through one ot' the press-magnets and then the other foreach reversal in the polarity of the curi-ent transmitted for actuatingthe escapement. rlhere are also provided at the transmitting-stationmeans for occasioning the completion of the shunt-eircuit around theresistance, iirst by means of a key upon the key-board corresponding tothe first of the type-wheels, and then by means of a key upon the secondof the key-boardsthat is to say, the one corresponding to the secondtype-wheel. In other words, for each reversal of the polarity of thecurrents employed at the moment the secondsystem of circuits areconnected with the main line, then an impression will be effected fromthe second type- It is evident that by properly adjusting thecircuit-closing devices ofthe transmitting key- IOO boards an impressionl'rom one type-wheel will be effected immediately after an impressionhas been taken from the other, and that two such succeeding impressionsmay be taken during the transmission of an electric current ot' onepolarity only. For the purpose of thus insuring that the circuits shallbe complete at the transmitting-station first through the one and thenthrough the other of the two transmitting 'key boards, two additionalpolechanging devices may be employed, each having itsconducting-segments oi' approximately lhalt-the width ot' the segmentsof the main These additional polel pole-changing device. changingdevices are respectively applied to the two transmitting` key-boards,the contactbrushes being respectively connected with the keys, while thecircuit-closing arms which are designed to revolve beneath the keys areconnected with the main line around the artificial resistance. Theconducting-segments of the additional pole-changing device which isapplied to one of the transmitting key-boards are so connected that theywill make contact with their contact-brush at the same time thecorresponding segments of the main polechanging devices make theirsuccessive contacts with their contact-brush. The contact segments ofthe second additional pole-chan ging device are, however, so placed withrespect to the contact-brush applied thereto that the contact betweenthe same and the brush will be during the latter half ot' the period ofcontact which is made between the corresponding segments ol" the mainpole-changing device and its brush.

The keys which are employed l'or completing the connections ofthe branchcircuits around the resistance are preferably constructed so that theymay be independently thrust into the path ot' a revolvingcircuit-closing arm, and they are also so constructed that this armwill, by striking against them, not only complete thecircuit-connections, but, without having its movement intcrrupted,willreturn them to their normal position. It will appear, however, that itwill not at any time be necessary l'or both circuit-closing arms to besimultaneously in contact with their respective keys. It is preferable,therefore, that the one contact-arm should be at such a distance behindthe other with reference totheir respective series of keys that thecontact ot' one of the circuit-closing arms with any key may occurimmediately after the other .contact-arm has separated i'rom thecorresponding key upon the other key-board. ln other words, while onecontact-arm is passing beneath a key upon its key-board the remainingarm will be be tween two of the keys upon the remaining board, so that'it is impossible for both arms to simultaneously make contact with anyof the circuit-closing keys.

rllhe type-wheels ofthe receiving-instrumcnt are preferably similar toeach other, each consisting of a large wheel bearing any desired numberof characters, preferably one hundred and forty-four. rlhesc charactersare preferably, moreover, arranged in a sequence, and are repeated withafrequency depending upon the order of succession and the frequency withwhich they are usually employed in the class ot' work in connection withwhich the instruments are designed to be employed. A single escapementis employed for conveying a stepby-step movement ot' these type-wheels,and this escapement is actuated by means of the alternating electricimpulses transmitted by the main pole-changingdevice. Y,

Upon the shaft carrying the type-wheels are carried two circuitcontrolling devices. each consisting of a series of alternatingconducting and nou-conductin g segments, in number corresponding to thenumber ot' segments employed in the main pole-changing devices of thetransmitter. The contact-segments are connected with the main line,while the coutact-brushes which are applied to these circuit-controllingdevices are respectively connected with the coils of two press-magnets,

which are respectively designed to cl'tect im! the character employedfor actuating the escapement, and through the second electromagnetduring the period occupied by the latter halt' of that same impulse, sothat each incoming current of a given polarity will find its way to theearth, iii-st through one electromagnet and then through the other. Itthe strength of such a current be increased by shunting the resistanceat the transmittingstation, the electro-magnet which it traverses willbe vitalizcd, and an impression will be effeeted from the correspondingtype -wheel. Such an impression Vwill be effected, as has already beenshown, from the particular typewheel corresponding to the key-boardthrough which the increase in strength was occasioned, and, thetype-wheel being organized to revolve in unison with the circuit-closingarms, the particular type printed will correspond to the particular keydepressed.

rlhe escapement device employed for permitting the step-by-step movementofthe typewheels is such that the type wheels will advance continuouslyduring the movement ol" the escapement-anchor from one limit to theother of its vibration. lVhen, therefore, an electric impulse of thecharacter employed for actuating the same is iirst transmitted throughthe coils of the escapement-controlling electromagnet, the type-wheels,and also the circuitcontrolling devices, advance, and they continue toso advance until the armature has IOO IIO

completed its entire movement in a given direction.

The circuit-controlling devices are so organized that the completion ofthe main-line connections will be through one of the printingmagnetsduring the iirst portion of this movement, and through the secondprinting-magnet during thelatter half of its movement. ltwill appear,therefore, that the impressions from at least one of the type-wheelsmust be effected while the type-wheels arein motion. This is, in fact,accomplished; and for the purpose of so doing without retarding themovement of the type-wheels and without blurring the impressions it ispreferable to construct the platen and its supporting-lever in such amanner that its directionof motion shall be the same as that of therevolution of the typc-wheels,instead of in the opposite direction.

lt will be understood that characters may be printed from eithertype-wheel without ref-v erence to the other, and th-atitis notnecessary th at impressions should be taken from the two alternately;but either type-wheel may be printed from continuously. XVhen recordsare being made by both type-wheels during the same time, this isaccomplished without lessening the speed of operation of eithertypewhcel. For considering, for instance, that all the keys upon bothtransmitting-boards were depressed in succession, each printingleverwould operate to eit'ect an impression from the corresponding type-wheelof cach character upon the same in succession, and the time which mustnecessarily be allowed for the downward movement of each lever, after animpression has been made, will be ccupied by the upward movement oftheother lever, so that while impressions are being taken alternately fromthe two type-wheels the impressions from the second type-wheel will betaken during the time which must necessarily be consumed by the movementof thetirst printing-platen away from its type-wheel, and vice versa.

ln the accompanying drawings, whichillustrate the invention, Figure 1 isa diagram showing the general organization of apparatusand the circuitstherefor. Fig. 2 is a side elevation of the receiving-instrument, andFig. 3 is a plan view of the transmitting devices. Fig. 4. is asideelevation ofaparticular form ot' circuit-closing device, which is alsoshown in connection with Fig. 3. This igure also shows an elevation ofthe key-board, illustrating the construction ofthe keys. Fig. 5'is aside elevation ofthe type-wheel, and of a particular form ofcircuit-closing device for determining through which printing-magnet thecircuit of the main line shall be completed.

lefcrring to the figures, A .representsA a shaft, which is mechanicallyrevolved by any suitable means. Upon this shaft is carried apole-changing device, B, which is provided withl two insulated series ofcontact-segments, b and be;

Against the surface oi' the two series of contact-segments b and b2,respectively, rest two contact-brushes, c and c?, and these brushes arerespectively connected, by means'oi` conductors l and'2, with thepositive and negative poles, respectively, of two batteries, O and O2.The remaining poles of these batteries are connected with the earth at Gby means of a conductor, 3. A contact-brush, C, rests against theperiphery of t-he pole-changing device-B, and this brush makes alternatecontact with the segments of the two series b and b2, thereby causingelectric impulses of alternating polarity to be transmitted upon a mainline, L, through an artificial resistance, R. These electric impulsesare employed for actuating an cscapement device applied to thereceiving-instrument in a manner hereinafter described.

Two transmitting key-boards, K and Ki, are respectively located near thepole-changing device B. These key-boards are respectively provided withany desired number ot' vertically-movable transmitting-keys k and k2,respectively, and these keys are preferably constructed in a mannershown in Fig. et, so that when depressed they will remain so untilcaused by the contact of a circuit-closing arm,

E or El, to. again resume `their normal position. For this purpose thekeys are preferably rounded at their lower extremities, and they areprovided with frictional springs c', which iit into grooves c when thekeys are in their normal position. Vhen, however, the keys are presseddownward, the grooves are moved from beneath the ends of the springs,and the springs rest against the surfaces ot' the keys. Thecircuit-closing arms E, however, by striking against the extremity ofany depressed key, 7.', will raise the same without arresting the motionof the arm.

The circuit-closing arms are actuated and moved in unison with the shaftA and polechanging device B by systems of gearing-` F and F. The partsare so adjusted that for each revolution of the pole-changing device Beach of the arms E' and El will also complete a revolution beneath thekeys k. The number of keys upon each board is equal to the entire numberot' contact-segments b and If of thc circuit-changing devices The keysand the corresponding circuitclosing arms E are designed to cause anincrease in the strength of current normally transmitted to linewhenever it is desired to print a letter from the correspondingtypewheel ot' the receiving-instrument For this purpose two additionalpole-changing devices, D and Dl, are applied to the shaft A, and theyrevolve in unison with the pole-changing device B.

The devices D and DL are constructed with y contact segments d and di,which respectively IOO lIO

vice D are, moreover, so located with reference to the contact-brush C',which is applied thereto, that th ey will make contact with that brushat the moment the corresponding segment, Z1 or Z, of the device B makescontact with its brush C. Since, however, the segments d and d? are ofless width than the contactsegments b and b2, any particular segment dwill have passed from beneath its brush C when only a portion,preferably one-half, of the corresponding contact, b', has passed itscontactbrush C.

The contact-segments cl and d? of the polechanging device Dl are solocated with reference to the contact-brush C2 applied thereto that thatwill be brought into contact therewith at the moment the correspondingsegments d and dA2 of the pole-changing device D pass out of contactwith the corresponding brush, C. In other words, the parts are soadjusted that during the first half ofthe contact of any segment b withthe brush C a corresponding segment, d, of the device D will be i`ncontact with its brush C, and during the latter half'of the contact ofthe brush C with the segment b the corresponding contact-segment d ofthevpolechanging device D2 will be in contact with the contact-brush C2,so that there will be for each alternate contact of the brush C twoalternating contacts of the brushes C and Cl.

The series of contact-segmcnts d are connected with the 'positive poleof the battery O by means of two contact-brushes, c and c", and theconductors et and 5, while the segments cl2 are connected by means ofthe brushes c5 and c and conductors 6 and 7 withthe negative pole of thebattery O2. The contact-brushes C and C2 are respectively connected,through conductors and 9, with the series of keys lr, carried by the twotransmitting key-boards K and KL. rllhe contact-arms E and E2 of thesetwo key-boards are respectively connected, through conductors l0 and 11,with the main line L at a point, l2, beyond the resist ance R. Two openbranch circuits are thus formed around the resistance It. Either ofthese circuits may be completed by means of a key, 7i', being depressedat the proper moment. Vhen such a circuit is completed, an increase'inthe strength of the current reaching the main line L will be occasionedby reason of the shunting of the resistance It, and, as has already beenshown, the circuit which is thus completed will be from the same batteryas that which is connected with the main line at the same time throughthe pole-changing device B. It will also be understood that the increasein the strength thus occasioned by the depression ot' any particular keywill continue for one-half the time occupied by the impulse itself, andit will occur during the rst or the last half of the impulse,accordingly as it'is occasioned by a key upon the board K or the boardK2.

The only remaining point which it is necessary to observe with referenceto the transmitting key-boards is that the positions of the arms E andE2 with reference to the keys k and k, respectively, are such that whenthe arm E is passing beneath any one of the keys of the board K the armEl is passing across the space intervening between two keys 7J! ot' theboard K2, so that whatever keys upon either of the boards be depressedboth arms will not simultaneously make contact with any oct' these keys.Each arm, however, will be in a position to makesueh contact at themoment the connections of the corresponding branch circuit are completedtherewith by means of the corresponding pole-changing dcvice, D or D2.

It will be found convenient to arrange the transmittingkeys in themanner illustrated in'Fig. lthat is to say, in curved radial lines orseries, each series containing any convenient number-say four keys. rlhenumber ot' keys in each board is preferably equal to the number of typeor corresponding characters carried upon the corresponding type-wheel,and they are for convenience arranged in an order ot' succession which,in practice, is found best suited to secure the greatest speed inoperating-that is to say, the letters which are found to succeed eachother most freqently in the class of work to which it is designed toapply the instrument are made to succeed each other in the transmitterand upon thetypewheel, and each letter is repeated a number of timesproportion ate to the frequency of its use. The distances between theradial lines which pass-through the centers of the respective keys ofeach board are preferably equal, so that the time occupied by thecircuit-closing arm in passing from one key to the next is the samethrough the board, and, as already stated, the circuit-closing arms arepreferably so arranged that when one of the same is passing beneath anygiven key, the other circuit-closing arm is midway between two of thekeys on its board.

rPhe receivi11g-instrument is provided with two type-wheels, N and X2,respectively, corresponding with the key-boards K and I. These wheelsare mounted upon a shaft, l), which may be propelled by a spring orweight, or in any other suitable manner. Upon the shaft I is placed astar-wheel, Q. The movements of the star-wheel, and thus of the shaftl?, are controlled by means of an anchor-escapement, Q, and anelectro-magnet, M.,which is provided with an armature, q', capable ofbeing vibrated by means of alternating electric impulses transmitted bythe pole-changing device B.

The electro-magnet lll is constructed with a set of coils, m, which arewound in the manner usually adopted for producing magnetism of oppositepolarity in the confronting poles of the cores o and o2. TheconductorLleads to one terminal of the coils m of the electro-magnet M,and the remaining termi nal of these coils is connected with the shaftl) through a brush, p', resting thereon. Each set of cores o and o2 is.however, preferably provided with additional coils mi and in,respectively, which are connected with the opposite poles ofcorresponding local batteries, o and 0*, respectively. The currents fromthese batteries normally induce in the cores a given amount ofmagnetism, and the currents from the main line tend to increase thestrength of the magnetism induced in one set ot' cores, '0, and todecrease or neutralize the amount in the opposite cores, 02, or viceversa, accordingly as the currents are of 011e polarity or the other.rllhere will therefore be an excess of attraction exerted upon thearmature q by one set or the other of the cores, accordingly as thecurrent from the main lineis in one direction orthe other, and thisexcess will cause the soft-iron armature to vibrate in a manner Wellunderstood. The movements of the armature thus occasioned permit astep-by-step movement of the typewheels; but owing to the constructionof the teeth ofthe scape-wheel and the pallets of the escapement-anchor,the movements ofthe typewheel shaft will be continuons during themovement of the cscapement-armature from one extremity to the other ofits vibration.

Upon the shaft I are carried two circuitcontrolling devices, S, eachconsisting of a series of contact-segments, s, which alternate withintervening non-conducting segments The segments s are of such a lengththat they will bein contact with a corresponding brush, TorT, duringtherevolution of the type-Wheel, through a period corresponding to the timeduring which a corresponding contact-segment, d, ofboth D and Dit ofthetransmittinginstrument is in contact with its contact-brush. The brushesare, moreover, so applied to the circuit-controlling devices S and S2,respectivcly, that contact will be made through one and then through theother, but at no time with both simultaneously. The brushes T and Tl arerespectively connected with the earth through conductors 13 and 14, inwhich are included two electro-magnets, U and U2, respectively. Thecircuit will therefore be completed during the revolution of thetypewheel shaft, first through one and then through the other of theelectro-magnets U andl Ui, and the times during which such completion.occurs are made to correspond to the times when the connections ofthebranch circuits of the transmitter are completed by the devices D andD2 with the key-boards K and K2, respectively. lf any key upon the boardK be depressed,the moment the circuit-closing arm E strikes that key theconnections of the battery Oor O, which may be connected with the mainline through the device B,Will be completed around the resistance It andat the receiving-station through the shaft P, segment s', brush T,andelectro-magnet U', and an impression n'ill be taken fromthe type-wheelcorrcspondingto the key which is depressed,

itbeing assumed 'that the devices have been so placed that the positionof the circuit-closing arm with reference to the keys of its keyboardcorrespond to the position of the type upon the type-Wheel withreference to the printing platen. In like manner any key upon thekey-board K2 may be employed for effecting an impression ota charactercorresponding thereto from the type-Wheel Nl.

rlhe electro-magnets U and U2. are designed to .respond only to electricimpulses of increased strength, such as are occasioned by shunting theresistance It, and they will therefore act to eiiect impressions onlywhen a transmitting-key has been struck by the corresponding arm, E.

It may here be observed that in orderV to occasion the desired movementof the circuitcontrollers S and S2, for the purpose of placing the twoelectro-magnets U and U2 successively in circuit during each impulse ofalternating polarity, it is not only necessary that the type-wheel shaftshould be moved, but, unless other special means are provided, it willbealso necessary that the type-Wheels themselves shall change theirposition during the continuance of each electric impulse.

In practice it is desirable to so construct the apparatus that thetype-wheel N Will be in position to print when the armature q is inaposition about midway. bet-Ween the confronting cores o and o, whilethe type-Wheel N2 Will be in position to print when the armature is adjacent to either of the cores o or 0". It will, moreover, appear that theimpression must be taken While the type-Wheel is in motion. This may bereadily accomplished, especially from a Wheel of the diameter which itis.proposed to employ in this instrument-namely, about four and onequarter inehes-Without difficulty. The armatures u of theelectro-magnets U and U are carried upon levers ui, and these leverscarry the printing platen u. When either electro-magnet U is vitalized,the corresponding platen will be moved in the direction indicated by thearrow, and the direction of the curve which it describes will he in thesame direction as the direction of revolution of the wheel. y reason ofthis construction no material retardationof the wheel will. beoccasioned, but, on the contrary, an accelerating force will be appliedthereto. Since, however, it is necessary that the type-Wheel N shall bein a position more advanced than th at in which it is when an impressionis taken from the type-wheel N', it will be necessary to pla-ce theprinting-platen a, which is applied to the t ype-Wheel N2, in apositioncorrespondingly advanced, so that it may strike the type.

In practice it may be found desirable under some circumstances todispense with the polechanging devices D and DI, and to rely merely uponthe contact of the arms E with the respective keys 7s for obtaining anincrease in the strength of current of the required duration when it isdesired to print. Inv practice IOO the duration of the increase ot' thestrength ot' the current thus obtained would be sufticientl y short toeffect the same results as are insured by the use of the pole-changingdevices D, it being understood that the circuit-closing arms act toforce the keys upward out of their path automatically, thereby breakingcontact witlr out interrupting the movement of the arm.

Referring now to Figs. 3 and 4, a description will be given of aparticular form of circuit-closer which is sometimes employed inconnection with the transmitting-instrument.

Upon the shaft A is carried a toothed wheel, V, which gears withapinion, fw', carried upon.a suitable arbor, wi. A contact-disk, wi, isalso carried upon the shaft A, and against the opposite surfaces of thesame rest two insulated contact-disks, fw and wi', respectively- Each ofthese disks is provided with a series of contact-pins, w, projectingfrom the surface toward the intervening disk, w". Upon the revolutionofthe shaft A the disks 104 and Awi are also caused to revolve, and thepins w are successively placed in connection with the disk w. Therelative rates of revolution of the two disks depend upon the relativesizes of the wheel IV and pinion ai. IVhen seventytwo keys are employed,it is preferable to cause the disks w" and mi to complete sixrevolutions for each revolution of the disk w, There should then Vbe sixcontact-pins w upon each of the disks w and w", so that for everyrevolution ot' the shaft A there will be seventy-two contacts made withthe disk in". The positions of the contact-pins fw upon the disk walternate with those of the pins upon the disk ai, and the positions ofthe disks w" and fw Vwith Vreference' to the intervening disk w are suchthat only one pin is in contact with the disk w at any time. Thepositive and negative poles of two batteries, O and O2, are respectivelyconnected with the disks w and uw", and by means of conductors 14 and 15the remaining poles of those batteries are connected with the earth at Gby means of a conductor, 16. The disk w3 is connected by a conductor,17, including the resistance It', with the main l'rne L, and alternatingelectric impulses are thus transmitted to line in the same manner asdescribed with reference to the pole-changing device I3.

For the purpose of completing the shuntconnections around the resistanceIt when it Y is desired to print, the keys It are connected by means ofconductors 18 and 19, respectively, with the main line L at a point, 23,beyond the resistance It, while the circuit-closing arms E and El areconnected through conductors 2l and 22, respectively, with thecouductors 14 and 15. The conductors 2l and 22 may, however, if desired,lead directly to the conductor 17. The contact of either of the 4armswith a key will cause the impulse being transmitted to line to beincreased in strength by reason of the shunting of the resistance R inthe manner already described. The additional pole-changing devices D andD are in this instance dispensed with, andthe contacts of the arms withthe keys are relied upon for determining the length of the increase instrength of the impulses, as already described.

The advantages secured by this construction of pole-changing deviceconsists, especially, in the long surface contact secured between thedisk wi" and the points 'uri The pins f1.0 may, if desired, be mountedupon yielding springs wl, for the purpose of permitting them to yieldslightly when brought in contact with the disk le.

A form of circuit-controlling device which it may be found convenient toemploy at the receivingstation consists of a disk, Y', carried upon anarbor, p, which is connected through a system of gearing, p, with theshaft I. This disk is provided with a series ofcoutaet-scgments, y,which are sut'iicient in number to afford seventy-two contacts with eachof two contact-rollers. Yl and Y, for each revolution of the shalt I?.Two contact brushes or rollersT2 and Yi, are respectively connected,through the electro-magnets U and U2, in the manner described withreference to Fig. 1. rIhese brushes are so located that the one isbrought into contact with a conducting-segment or contact-point at themoment a correspending segment is carried, out of contact with the otherbrush.

The operation of this pole-changing Vdevice is in other respects similarto that described in connection with Fig. 1.

In the foregoing description the number of type carried by thetype-wheel, as also the number of keys in each key-board, has beenreferred to as seventy-two, and the other related parts have beendescribed as adapted thereto; but the employment of one hundred andforty-four keys upon each key-board and the same number of type uponeach type-wheel, or in fact any desired number, is contemplated.

Any suitable form of unison device may be employed for securingsynchronism between the transmitting and receiving instruments.

It is evident that any desired number of instruments may be placed incircuit. For instance, the conductor leading to the earth at Gr2 in Fig.l might be led to and through another instrument, which would operate inthe same manner as that described.

In another application for Letters Patent led by me April 1S, 1884,Seria-l No. 127,065, and entitled improvement in multiplex telegraphs7 Ihave shown and described certain organizations of apparatus which insome particulars resemble the devices, apparatus, and method ofoperating the same shown and described in this present application, andI do not therefore herein claim anything shown, described, andspecifically claimed in the said other application and not specificallyclaimed herein.

I claim as my invention- IOO IIO

l. rlhe eombinatiomsubstantially as hereing device adapted to transmitelectric iminbefore set forth, of a series of transmittinginstruments, aseries of receiving-instruments, a device adapted to transmitalternating electric currents to said receiving-instruments, and acircuit-changing device actuated by said alternating currents, andadapted to complete the connections of said main line successivelythrough each of said receiving-instruments during the transmission ofeach of said alternating currents.

2. The combination, substantiallyas hereinbefore set forth, of atelegraph main line, two transmitting devices, tworeceiving-instruments, means for placing said transmitting devicesalternately in connection with one terminal of said main line, apole-changing device transmitting an electric impulse for beingtransmitted during a portion of its continuance, and tworeceiving-instruments, which respectively alternately connected with theremaining terminal of said mainline during the continuance of eachalternating impulse.

4. The combination, substantially as hereinbefore set forth, of a mainline, means, sub` stantially such as described, for transmittingalternating electric impulses thereto, means, substantially such asdescribed, for varying the strength ot' different portions-of each ot'said impulses, and two or more receiving-instruments respectivelyactuated by such variations.

5. The combination, substantially as hereinbefore set forth, of a mainline, a pole-changing device for transmitting alternating electricimpulses upon said main line, two revolving circuit-closing arms, twokey-boards, to which said circuit-closing arms are respectively applied,means, substantiallysuch as described, for causing the keys of either ofsaid boards to occasion a variation in the strength of the impulse beingtransmitted to line when they are placed in the path of thecorresponding circuit-closing arm, and two receivinginstrumentsrespectively adapted to respond to the variation of current caused bythe two keyboards.

6. The combination, substantially as hereinbefore set forth, ofa mainline, a pole-changpulses of alternating polarity upon said main line,two transmitting key-boards, two supplementary pole-changing devicesrespectively adapted to place said key-boards successively in circuitwith the said main line during the transmission of each of saidimpulses, and means, substantially such as described, for continuing theconnections thusformed from either key-board to one or more batteries.

7. The combination, substantially as hereinbefore set forth, of a mainline, apole-changing device adapted te transmit alternating electricimpulses to said main line, an artificial resistanee, through which saidimpulses are transmitted, two shunt-circuits around said resistance, andmeans, substantially such as described, for completing the connectionsof either or of botn of said shunt-circuits at will during t-hetransmission of any one of said alternating electric impulses.

8. The combination, substantially as hereinbefore set forth, of a mainline, a battery, a pole-changing device adapted to transmit alternatingelectric impulses from said battery upon said main line, an artilicialresistance through which said impulses are transmitted,

two open branch circuits extending from said battery around saidresistance, means,4 substantially such as described, for completing theconnections of each of said branch circuits successively during thetransmission of any one oi' said alternating electric impulses.

9. The combination, substantially as hereinbetoreset forth, with atelegraphic main line, means for transmitting alternating electricimpulses of a given strength upon said main line, and means,substantially such as described, for varying the strength ot' differentportions of each of said impulses, of two or more receiving electro-magnets an escapement device serving to placeA said instruments incircuit with said main line successively during the transmission of asingle of said impulses.

l0. The combination, substantially as here- IOO IIO

inbefore set forth, with a telegraphie main line, means, substantiallysuch as described, for transmitting alternating electric impulses uponsaid main line, and for varying the strength of different portions ofeach of said impulses, of two receiving electromagnets, two type-.wheelsto which said magnets are respectivel y appliechan escapement deviceactuated by said alternating impulses, and a circuit-controlling deviceoperating to connect said main line through one or the other of saidelectro magnets during the tansmission of each of said impulses.

1l. The combination,substantially as hereinbetore set forth, of twoelectro-magnets, two printing-platens actuated by said electro-inagnets,two type-wheels to which said printingplatens are respectively applied,an escapement device for said type-wheels, and a circuit-controllingdevice serving to complete a circuit-connection through each of saidelectro-magnets in succession during the movement of said escapementdevice in one direction.

12. The combination, substantially as hereinbefore set forth, of a mainline, means, substantially such as described, 'for transmit-tingalternating electric impulses upon said line, an escapement deviceactuated by said impulses, two type-wheels, two electro-magnets forrespectively effecting impressions from said type-wheels, acircuit-controlling device actuated by said escapement device,andserving to complete the connections of said main line through each ofsaid electro-magnets in turn during the transmission of a singleelectric impulse.

13. rEhe combination, substantially as hereinbefore set forth, withanreseapemcnt device, electro-magnets for actuating the same, means,substantially such as described, for transmitting electric impulsesthrough the coils of said electro-magnets,thereby actuating saidescapement device, two type-wheels, two electro-magnets for effectingimpressions therefrom, which electro-magnets are adjusted not to respondto the impulses normally employed for actuating said escapement device,and means, substantially such as described, for completing thecircuit-connectionsfrom said escapcment-magnets to said type-wheelmagnets successively during the transmission of a single impulse, andmeans, substantially such as described, for varying the strength of aportion of said impulse when it is traversing the coils of either ofsaid type-wheel magnets.

14. The combination, substantially as hereinbefore set forth, of atelegraphic main line,

two transmitting key-boards, means for placing the same alternately inconnection with said main line, two type-wheels, and means,

substantially such as described, for actuating them, two electro-magnetsfor effecting impressions from said type-wheels, respectively, andmeans, substantially such as described, for completing the connectionsof said main line through the coils of said electro-magnets alternatelyand simultaneously with said transmitting 4key-boards. y

15. The combination, substantially as hereinbcfore set forth, of atelegraphic main line,

two revolving circuit-closing arms connected therewith, two series ol'keys respectively applied to said circuit-closing arms,and adapted tocomplete circuit-connections with said main line, a pole-changing deviceconsisting of a contact-plate moving with said arms, two contact-disksrevolving upon opposite sides of said plate, and a series ot'contact-points carried upon each of said disks, which contactpoints arealternately placed in connection with said contact-plate.

16. The combination, substantially as hercinhefore set forth, of one ormore revolving circuit-closing arms, a series of keys applied to eachofAsaid circuit-closing arms, a polechanging device consisting of acontact-plate revolving with said arm or arms and two insulated seriesof'yielding contact-points revolving upon opposite sides of said plate,

which contact-points are alternately placed in connection with saidcontact-plate.

17. The combination, substantially as hereiubefore set forth, with arevolving circuitclosing arm and a series of transmitting-keys to whichsaid arm is applied, of a pole-changing device consisting of acontact-plate revolving with said arm and two series of contact-points,which series are revolved at a greater rapidity than said contact-plate,and which are caused to make alternate contact with the opposite sidesof the same, substantially as described.

1S. The combination, substantially as hercinbefore set forth, of anescapement device, a type-wheel shaft, two typcwheels moving with saidescapcment device, two electro-magnets for effecting impressions fromsaid typewheels, and a circuit-controlling device for completing theconnections of an electric circuit alternately through saidelectro-magnets, which device consists of a segmental wheel connectedwith and revolving at a greater rapidity than said shaft, and Atwocontact-rollers, which are respectively connected with the coils of saidelectro-magnets.

In testimony whereof I have hereunto subscribed my name this 13th day ofMarch, A. l). 158i.

CHAR-LES G. ZURKE.

Vitn esses:

DANI.. XV. EDGEooarc, Cimnnns A. TERRY.

